core.py 文件源码

def get(cls, *args, **kwargs):
        """Generic 'smart' get function. Does different things based
        on number of arguments.  Some would call this a 'not smart'
        idea but we are not asking them.

        Single positional argument and no kwargs:
          args[0] is not of type ClauseElement:
            Looks up model by primary key of model specified by cls.PKEY
          args[0] is of type ClauseElement:
            Adds the clause emelemt to a where clause for a query on cls.

        Anything Else (any combination of multiple args and any kwargs):
          Converts all kwargs to clause elements, adds the args (all
          should be clause elements), and passes them together in as
          the where filter (all combined with AND) to a query on cls.
        """
        if len(args) == 1 and not isinstance(args[0], ClauseElement):
            terms = [getattr(cls, cls.PKEY) == args[0]]
        else:
            terms = list(args) + \
                [getattr(cls, k) == v for k, v in kwargs.items()]

        obj = cls.query.filter(*terms).first()
        if obj:
            return obj

        cause = dict(kwargs) if kwargs else list(args)
        raise ApiException(
            "Failed to get %s: %s" % (cls.__name__, cause),
            cause=list(cause.keys()) if kwargs else cause)